Glabrous; stems 2–13 dm, 4-angled or very narrowly winged; lvs sessile, lanceolate, narrowly oblong or oblanceolate, acute or acuminate, obscurely crenate, either rounded or narrowed at base, the larger 5–10 cm, the upper progressively reduced and the uppermost sometimes bract-like; pedicels solitary in the upper axils, divergent, 2–4.5 cm, at maturity erect or up curved; bractlets none; cal 10–16 mm, the short lobes broadly ovate to semicircular at base, abruptly prolonged into a short, nearly linear tip; cor blue, 2–3 cm; 2n=24. Wet woods and swamps, and open marshy places; Que. and N.S. to Sask., s. to Ga., La., and Okla. Plants of tidal mud from Que. to Me., with considerably shorter internodes, pedicels, and cal have been distinguished as var. colpophilus Fernald.
Can be grown by seedlings. Seeds needs stratification.